Climate crisis, ‘El Niño’ and lack of investments: the dangerous cocktail after the destructive floods in southern Brazil

An international team of scientists has prepared something like an autopsy of the tremendous floods that southern Brazil suffered between April 24 and May 4, which affected 90% of the state of Rio Grande do Sul. There were at least 172 fatalities (in addition to four dozen missing) and more than half a million people had to leave their homes at some point. These researchers from Brazil, the United Kingdom, Sweden, the Netherlands and the United States conclude that human-caused climate change has made this extraordinary event of such intense rain twice as likely and between 6% and 9% more likely. intense than in a world without global warming. But, in addition, the phenomenon of The boya natural pattern that causes water surface temperatures in tropical areas of the Pacific to rise, which has effects on global climate.

During the presentation of the report, Regina Rodrigues, researcher at the Federal University of Santa Catarina, defined floods as “one of the most significant environmental tragedies.” But the cocktail that made these rains so destructive is completed by the lack of investment in the maintenance of key anti-flood infrastructure, such as pumping stations and floodgates. “Reports indicate that the maintenance and financing of the Porto Alegre flood protection system [la capital del Estado] have been significantly reduced,” points out this study led by the World Weather Attributiona group of scientists specialized in rapid studies that evaluate the influence of global warming on extreme weather events.

On a planet subjected to climate change, these phenomena also increase in number and intensity, so prevention and adaptation are key. And in that field something also failed in this case analyzed. “Investments in flood prevention decreased from 2021 to 2022, without funds being allocated in 2023,” notes the analysis on Porto Alegre. “In addition, many components of the system, including pump stations and gates, have been poorly maintained or are not functioning.”

The report suggests that the absence in recent decades of events as extreme as the one experienced at the beginning of the month could be behind the relaxation when it comes to maintaining defense infrastructure against floods. In fact, researchers maintain that a phenomenon of this intensity and duration is expected to occur only once in between 100 and 250 years in the current climate. Currently, the planet is 1.2 degrees Celsius warmer than before the Industrial Revolution, when humans began to burn fossil fuels on a large scale, the main cause of this crisis. The researchers maintain that if we reach 2 degrees of warming, something that can happen in just two or three decades unless emissions are stopped quickly, rain events similar to what southern Brazil has suffered “will be twice as many.” probable than at present.”

Lincoln Alves, from the National Space Research Institute of Brazil, explained that what happened at the beginning of May in the south of the country is consistent with what studies on the impact of climate change already pointed out. The last major review by the IPCC, the international panel of scientists that works under the umbrella of the UN, already pointed to an increase in the frequency and intensity of heavy rainfall events in this region. The further warming progresses, a hardening is expected because, as Alves explained, the atmosphere will be more loaded with humidity.

37,000 ‘climate refugees’

Rio Grande do Sul will take a long time to recover. Rivers overflowed, dozens of cities were completely flooded and thousands of houses were destroyed or unusable. An infrastructure as important as the Porto Alegre international airport remains partially flooded and will reopen, at the earliest, in August. According to the most recent report from the Civil Defense, since it started to rain, almost 580,000 people were forced to leave their homes; Of them, more than 37,000 continue to sleep in makeshift shelters in schools or sports centers. There are many who are beginning to define them as climate refugees.

The federal government has already mobilized 62.5 billion reais (more than 11.8 billion dollars), but the reconstruction tasks have barely been able to begin. Until a few days ago there were still cities on alert and many neighborhoods are still under water. For now, the priority is to build four “provisional cities” for families who lost everything.

“Although Rio Grande do Sul is often perceived as a prosperous region, it still has significant pockets of poverty and marginalization,” notes the report presented this Monday. “Low income has been identified as an important factor in the impact of the floods,” he emphasizes. As Maja Vahlaberg, a climate change expert at the Red Cross and another of the authors of the study, recalled, uncontrolled urban planning has also had an impact as there are a large number of homes built in flood-prone areas. “Informal settlements, indigenous villages and predominantly quilombolas (descendants of enslaved Africans) have been seriously affected,” the researchers highlight.

Something similar happens with deforestation: by eliminating the vegetation cover, the avenues do not find resistance during floods. “While environmental protection laws exist in Brazil to protect waterways from construction and limit changes in land use, they are not applied or enforced consistently, leading to the invasion of lands prone to flooding and therefore increases the exposure of people and infrastructure to flood risks,” the World Weather Attribution document concludes.

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